The present invention relates to an electron beam exposure apparatus and, more particularly, to an electron beam exposure apparatus for irradiating electron beams from an electron source and drawing a pattern on a wafer or on a mask or reticle using the electron beams, its control method, and an electron beam irradiation device suitable for the electron beam exposure apparatus.
An electron beam exposure apparatus includes a point beam type that uses a beam having a spot-like sectional shape, and a variable rectangular beam type that uses a beam having a rectangular sectional shape of a variable size.
The point beam type electron beam exposure apparatus is used for only research and development purposes since it draws using a single electron beam and has a low throughput. The variable rectangular beam type electron beam exposure apparatus has a higher throughput than the point type apparatus by about one to two orders of magnitudes but also suffers many problems of throughput since it basically draws using a single electron beam, when a pattern including fine patterns as small as about 0.1 .mu.m at a high degree of integration is to be exposed.
As an apparatus that can solve such problems, a stencil mask type electron beam exposure apparatus is known. In this apparatus, the pattern to be drawn is formed as a pattern through holes on a stencil mask, and is transferred onto a reticle surface via a reduction electron optical system by illuminating the stencil mask with an electron beam. Also, a multi electron beam type exposure apparatus is known. In this apparatus, a substrate having a plurality of apertures is illuminated with an electron beam, a plurality of electron beams coming from the plurality of apertures are irradiated onto a reticle surface and are deflected to scan the reticle surface, and these electron beams are individually turned on/off in correspondence with the pattern to be drawn, thereby drawing a pattern. Both the apparatuses can improve the throughput since the area to be exposed, i.e., the exposure area is broader than the conventional apparatuses.
However, in the stencil mask type electron beam exposure apparatus, if the electron beam that illuminates the stencil mask is nonuniform, the transferred pattern is distorted. On the other hand, in the multi electron beam type exposure apparatus, if the plurality of electron beams have intensity variations, again the drawn pattern is distorted.